Malicious PDF — malware analysis report

Static analysis result for SHA-256 11606bebab95e935…

MALICIOUS

PDF

83.0 KB Created: 2021-09-15 20:28:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ecacab07d7c1c17b79d52c369672a05d SHA-1: a29209a9248818b912b84d95805d8caaa4bc3efd SHA-256: 11606bebab95e935c1e67f47f816bf9304e79592e96fcc089386a674d326fb6b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable domains and are likely part of a link farm designed to redirect users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a high volume of links to distinct, potentially disposable hosts, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://varosom.hu/userfiles/files/69008945434.pdf In PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/fodabukuzibo.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/63873357806.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614080007e7ca---99263309520.pdfIn PDF document text
    • http://klaaswester.nl/img/file/mojixel.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/47454381477.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/r6v4n5r1a84nq6mlljb6u2lt36/19814906937.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/raxuvafanoku.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/53971579331.pdfIn PDF document text
    • http://kamakuralosgatos.com/uploads/files/3856065239.pdfIn PDF document text
    • https://careerexpo.alljobsinliberia.com/ckfinder/userfiles/files/89619043130.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/gosijitosiduxinaka.pdfIn PDF document text
    • https://olivierdaulte.com/ckfinder/userfiles/files/jovokuso.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/68728135462.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/dulefasijirujimukuvalafus.pdfIn PDF document text
    • https://inprovitargentina.com/ckfinder/userfiles/files/rogudonajeminajakubos.pdfIn PDF document text
    • http://12shio5.com/contents/files/wiruzama.pdfIn PDF document text
    • http://thefarmatarapahoecounty.com/userimages/38148860103.pdfIn PDF document text
    • http://liveranigioielli.it/userfiles/files/nevukifinelutefas.pdfIn PDF document text
    • https://chulintemple.house-well.com/CKEdit/upload/files/xixuwilevadi.pdfIn PDF document text
    • http://onthebroadway.com/CPD/adminpanel/upload/file/radarikomi.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/rufewu.pdfIn PDF document text
    • https://music-group-store.com/upload/files/33414327882.pdfIn PDF document text
    • http://ucinnovation.ru/admin/ckfinder/userfiles/files/juzekusek.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/fakotur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=android+deleted+files+folderPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE9 10164 bytes
SHA-256: f93a8a77b7d9c44cf3c1a63f537f4390152453adf83dc7a2c33cd770523c5172
font_02_sfnt_off000111c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111C2 17072 bytes
SHA-256: f7dab0a864f6289738918879590cc60151b0902072b84ee47969999dca02dba7